The reading of electrical-energy meters has historically been accomplished with human meter readers who visit a customer's premises and manually document relevant information from the meter. Such readings have usually been limited to information regarding the electrical consumption of the customer. Over time, manual meter reading has been enhanced or eliminated through the use of meter reading systems. In one example of a meter reading system, a probe is held in proximity to and communicates with the meter. The communication between the probe and the meter is two way and involves an exchange of information beyond just the electrical consumption of the consumer. Today, for example, diagnostic information can be communicated by the meter reading system.
Information between an electrical-energy meter and a probe or other external device may be exchanged by two-way, optically isolated communications. In such cases, the electrical-energy meter will have an optical port with an optical transmitter and an optical receiver that communicate with the external device through a respective optical receiver and optical transmitter of the external device.
Various styles of optical ports have been developed for electrical-energy meters. One style was developed in North America in conformity with the American National Standards Institute (ANSI). Another style was developed in Europe in conformity with the International Electrotechnical Commission (IEC).
The ANSI optical port and the IEC optical port differ in a few significant ways. First, the transmitter and receiver on an ANSI optical port are positioned in an opposite manner from the transmitter and receiver on an IEC optical port. In particular, when facing an ANSI optical port on an electrical-energy meter, the transmit channel is on the right and the receive channel is on the left. When facing an IEC optical port, by contrast, the transmit channel is on the left and the receive channel is on the right. A second significant way in which ANSI and IEC optical ports differ is the mechanical interface between the electrical-energy meter and the external device. For example, though not required under IEC, an IEC optical port commonly may have a number of small posts that are used to help align and hold a probe of the external device in place for the communication exchange. A typical ANSI optical port does not have such posts. An ANSI optical port, however, has a “D” shape and protrudes from the face of the meter whereas an IEC optical port is generally flush with the cover of the meter.
Electrical-energy meter manufacturers have produced meter designs corresponding to the industry standard prevalent to the particular geographical area. This has led to the production and distribution of external devices configured to correspond to the electrical-energy meters. For example, in North America, external devices are configured to correspond to ANSI electrical-energy meters. In Europe, external devices are configured to correspond to IEC electrical-energy meters.
As manufacturers desire to increase market share while selling a single electric-energy meter design throughout the world, there is a need to provide a single electrical-energy meter design such that the meter is able to communicate with external devices constructed in accordance with various industry standards, such as ANSI and IEC.